1. Field of the Invention
The present invention relates to a module part and an electronic device having the mounting structure, and more particularly, to a module part such as a DCxe2x80x94DC converter to be mounted, e.g., onto a notebook-sized personal computer and electronic devices containing the module parts
2. Description of the Related Art
FIG. 5 is a cross sectional view of a conventional module part and a mounting structure of the module part. In FIG. 5, a module part 1 comprises a part-mounting substrate 2, connecting terminals 3 provided on one main face of the part-mounting substrate 2, and parts 4, 5, and 6 mounted on the other main face of the part-mounting substrate 2.
The part 4 has a larger height than any other part, and is provided with connecting terminals 4a. The connecting terminals 4a are soldered to wiring electrodes (not shown) formed on the other main face of the part-mounting substrate 2. As regards the parts 5 and 6, connecting electrodes are formed, for example, on the back sides thereof, and are soldered to wiring electrodes similarly to the part 4. The connecting terminals 3 provided on the one main face of the part-mounting substrate 2 are connected to the wiring electrodes formed on the other main face of the substrate 2.
The connecting terminals 3 are soldered onto the wiring electrodes (not shown) formed on one main face of the mother board 7, so that the module part 1 configured as described above is mounted onto the mother board 7.
FIG. 6 shows a cross sectional view of another conventional module part. In FIG. 6, the same or equivalent parts to those shown in FIG. 5 are designated by the same reference numerals, and the repeated description is omitted.
In FIG. 6, a module part 10 contains a part 12, which also has a large height, instead of the part 4 of the module part 1 shown in FIG. 5. Connecting terminals 12a are provided for the part 12. Moreover, the module part 10 contains a part-mounting substrate 11 having a first cutoff portion 11a with such a size that the part 12 can be placed therein, instead of the part-mounting substrate 2. The part 12 is placed in the first cut-off portion (hole) 1a of the part-mounting substrate 11 to be mounted. The connecting terminals 12a are soldered onto wiring electrodes (not shown) formed on the other main face of the part-mounting substrate 11.
The connecting terminals 3 are provided on the part-mounting substrate 11 similarly to the part-mounting substrate 2 shown in FIG. 5. The connecting terminals 3 are soldered onto wiring electrodes (not shown) formed on the one main face of the mother board 7, so that the module part 10 is mounted onto the mother board 7.
FIG. 7 is a cross sectional view of yet another conventional module part. In FIG. 7 the same or equivalent parts to those shown in FIG. 5 are designated by the same reference numerals, and the repeated description is omitted.
A module part 20 of FIG. 7 is provided with connecting terminals 21 formed on the other main face of the part-mounting substrate 2, instead of the connecting terminals 3 of the module part 1 shown in FIG. 5. The connection surface of each connecting terminal 21 in the height direction of each module part 20 is just level with the bottom of the part 4 in the height direction thereof. Here, the connection surface of the connecting terminal 21 means the surface thereof which is connected to the wiring electrode (not shown) formed on the mother substrate 22.
The part-mounting substrate 2 of the module part 20 configured as described above is placed into a second cutoff portion (hole) 22a formed in a mother board 22, the second cut-off portion 22a having such a size that the part-mounting substrate 2 can be placed therein. In this case, the connecting terminals 21 are soldered onto wiring electrodes (not shown) formed on the one main face of the mother substrate 22.
Referring to the module part 1 shown in FIG. 5, the part 4 having a large height is mounted onto the part-mounting substrate 2. Thus, the module part 1 itself becomes very high. Accordingly, problematically, when the module part 1 is mounted onto the mother board 7, the whole of a circuit portion containing the module part 1 and the mother board 7 becomes thick, which prevents reduction in the thickness of an electronic device using the mother board 7.
The part 12 of the module part 10 shown in FIG. 6 is placed in the cutting-off portion 11a of the part-mounting substrate 11 to be mounted. Accordingly, the height of the module part 10 itself is reduced by the thickness of the part-mounting substrate 11 compared to that of the module part 1 shown in FIG. 5. Thus, the thickness of the whole of a circuit portion containing the module part 10 and the mother board 7 is decreased by the thickness of the part-mounting substrate 11. However, the decrease in thickness is insufficient. A problem arises in that the thickness of an electronic device using the mother board 7 can be satisfactorily reduced.
Moreover, the height of the module part 20 itself shown in FIG. 7 is not different from that of the module part 1 shown in FIG. 5. Since the module part 20 has such a structure as to be placed in the second cut-off portion 22a of the mother board 22 to be mounted, the thickness of the whole of a circuit portion containing the module part 20 and the mother board 22, obtained after the module part 20 is mounted, is decreased by the thickness of the mother board 22 itself. However, problematically, the decrease in thickness is insufficient. Thus, reduction in the thickness of an electronic device using the mother board 22 can not be satisfactorily performed.
Accordingly, it is an object of the present invention to provide a module part of which the height can be decreased and which serves to reduce the overall thickness of a circuit portion containing the module part and a mother board, obtained after the module part is mounted, and an electronic device using the module part with the above-described problems being solved.
The module part or the present invention comprises: a part-mounting substrate having a first cut-off portion: a part having a large height and mounted to the part-mounting substrate such that at least portion of the part is placed in the first cut-off portion; and a mother board having a second cut-off portion and mounting thereon the part-mounting substrate such that at least a portion of part-mounting substrate is placed in the second cut-off portion.
According to the another aspect of the present invention, the module part comprises: a part-mounting substrate having a first cut-off portion: a part having a large height and mounted to the part-mounting substrate such that at least portion of the part is placed in the first cut-off portion; and a mother board having a second cut-off portion and mounting thereon the part-mounting substrate such that at least a portion of the part is placed in the second cut-off portion.
According to the present invention, the module part contains the part-mounting substrate having the first cutoff portion and the part having a large height placed in the first cut-off portion to be mounted, and the part-mounting substrate has such a structure as to be placed in the second cut-off portion of the mother board, and in the mounting structure of the module part, the part-mounting substrate is placed in the second cut-off portion to be mounted. Thus, the thickness of the whole of a circuit portion containing the module part and the mother board can be reduced.
Alternatively, the module part contains the part-mounting substrate having the first cut-off portion and the part having a large height placed in the first cut-off portion to be mounted, the part having a large height having such a structure as to be placed in the second cutoff portion of the mother board to be mounted, and in the mounting structure of the module part, the part having a large height is placed in the second cut-off portion of the mother board. Thus, the thickness of the whole of a circuit portion containing the module part and the mother board can be reduced.
The electronic device in accordance with the present invention, which uses the module part or the mounting structure of the module part in accordance with the present invention, can be reduced in thickness.